Conventionally, in such technical fields as industrial chemicals, medical supplies and cosmetic raw materials, a container is used for storage and transportation, the container accommodating a spout-equipped packaging bag, which is used for accommodating fluid content, inside an external container that is made of aluminum, steel, stainless steel, fiber-board and the like.
Such a container can be reused simply by taking out the used packaging bag from the external container and setting a new packaging bag into the external container. This leads to an advantage, for example, in that there is no need for washing as compared to cases of directly filling fluid content into an external container such as one made of steel without using a packaging bag. Accordingly, such a container is widely used as a container for industrial chemicals, medical supplies and cosmetic raw materials (for example, see Patent Documents 1 and 2).
The container disclosed in Patent Document 1 has an inner bag for accommodating a high purity chemical inside an external container, in which the external container is provided with an opening portion for filling and dispensing the high purity chemical and an opening portion for filling with a pressure regulation fluid, the inner bag is configured with an inner bag body and an inlet/outlet port for the high purity chemical, the inlet/outlet port is provided in communication with the opening portion of the rigid external container, an inner pipe is inserted from the outside of the inner bag for filling and discharging the high purity chemical, and stoppers are respectively fitted in the two opening portions with handles.
The inner bag disclosed in Patent Document 1 is made from a configuration that the inlet/outlet port is equipped on the inner bag body which is manufactured by cutting a cylindrical film to a predetermined length, which is manufactured by using an inflation molding machine, and a hole is made in the periphery of the cylindrical film that has been cut into a predetermined length, an inlet/outlet port passes through the hole, and fixation is performed at a bottom mounting ring portion by heat sealing.
In addition, similarly to the case of Patent Document 1, in the container disclosed in Patent Document 2, a packaging bag is equipped with a mounting member inside an external container (a metal drum in Patent Document 2), the mounting member is inserted into a bunghole that is made by cutting out (perforating) a first closure, and is attached to the first closure by use of a threaded ring or the like, and thereafter, is mounted to the metal drum main body.
As shown in FIG. 7, the inner bag disclosed in Patent Document 1 and the packaging bag disclosed in Patent Document 2 are provided with a periphery edge circumference that is heat-sealed to form a heat seal portion 501, a hole that is formed on a portion of the surface of the bag, the portion being off the center of the inner bag (or packaging bag) 500 and being closer to one short side of the bag, an inlet/outlet port (or mounting member) that is inserted into the hole, and are heat-sealed at a bottom mounting ring 503 provided at the bottom of the inlet/outlet port (or mounting member), thereby attaching thereto.    Patent Document 1: Japanese Unexamined Patent Application Publication No. H09-95565    Patent Document 2: Japanese Unexamined Patent Application Publication No. H05-505372